Right now I want to use the main outs for two sets of speakers. My main speakers are Yamaha hs8, I want to split the main out to simultaneously feed those and a soundbar for while I am laying in bed. They do not need independent volume control, I just want to know if my sonic quality will suffer from splitting the signal.

I cannot use the headphone output for this, I need my headphone levels to be controlled separately from the soundbar so it is unfortunately not an option.